The present invention relates to color correction, and more particularly to a chrominance transition corrector for restoring chrominance transitions after they have been degraded by a limited bandwidth channel.
In typical television video images, chrominance transitions from one color to another are matched to luminance transitions. After passing through a bandwidth limited channel with less chrominance bandwidth than luminance bandwidth, the chrominance transitions may no longer match the luminance transitions. The resulting loss of chrominance resolution degrades picture quality and also causes problems in chroma keying, which depends on chrominance detail to generate control or key signals.
Some previous approaches to improving chrominance sharpness have used peaking circuits, which speed up transitions. A flaw of this approach is that even those transitions which are supposed to be slow are speeded up. This results in inaccurate renditions of picture detail.
What is desired is a chrominance transition corrector that restores chrominance transitions to match luminance transitions after the chrominance transitions have been degraded by a bandwidth limited channel.